| **Summary of Significant Accounting Policies Product Warranty Liability (Details) (USD $)In Millions, unless otherwise specified** | 12 Months Ended                           |
|------------------------------------------------------------------------------------------------------------------------------------|-------------------------------------------|
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| **Movement in Standard Product Warranty Accrual [Roll Forward]**                                                                   |                                      |   |
| Balance at beginning of period                                                                                                     | $ 37us-gaap_ProductWarrantyAccrual        | $ 38us-gaap_ProductWarrantyAccrual |
| Warranty expense recognized                                                                                                        | 3us-gaap_ProductWarrantyExpense           | 3us-gaap_ProductWarrantyExpense |
| Warranty credits issued                                                                                                            | (5)us-gaap_ProductWarrantyAccrualPayments | (4)us-gaap_ProductWarrantyAccrualPayments |
| Balance at end of period                                                                                                           | $ 35us-gaap_ProductWarrantyAccrual        | $ 37us-gaap_ProductWarrantyAccrual |

| X                                                                                                                                                                                       |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
|------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Carrying value as of the balance sheet date of obligations incurred through that date and payable for estimated claims under standard and extended warranty protection rights granted to customers.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.15(5)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 15 -Subparagraph 5 -Article 9Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(5)) -URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249
+ Details**Name:**us-gaap_ProductWarrantyAccrual**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**credit**Period Type:**instant |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Represents the aggregate decrease in the liability related to payments to satisfy claims for standard and extended product warranties.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(2)) -URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249
+ Details**Name:**us-gaap_ProductWarrantyAccrualPayments**Namespace Prefix:**us-gaap_**Data Type:**xbrli:monetaryItemType**Balance Type:**debit**Period Type:**duration |
| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The expense charged against earnings for the period pertaining to standard and extended warranties on the entity's goods and services granted to customers.
+ References
Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 230 -SubTopic 10 -Section 45 -Paragraph 28 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 460 -SubTopic 10 -Section 50 -Paragraph 8 -Subparagraph ((c)(3,4)) -URI http://asc.fasb.org/extlink&oid=6398077&loc=d3e12565-110249
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